However concerns were starting to increase about the ability to model the dominant Fe-L emission in the IGrM by the available plasma codes. The first ASCA CCD spectra (with the SIS instrument) of the cores of cool core clusters, Perseus, Abell 1795 and the Centaurus cluster exposed the limitations of both the RS and MEKA [1]}, [2]} models [3]}, causing a major revision of the modeling of the Fe-L shell emission [4]} which later was incorporated in the MEKAL code. These concerns
were reinforced by the discrepancy between the low metallicity found also in the inter-stellar medium of elliptical galaxies and the super-Solar abundances expected just by stellar mass loss [5]}, [6]}.
